Plan the best time to shoot your subject. Shoot when the subject is highest in sky, when it transits the meridian. Shoot when the seeing is best, often just after sunset and just before dawn. Check the location of the jet stream. Don't expect great results if the jet stream is overhead or nearby.

Use a tracking mount. If it is a computerized altazimuth mount, make sure it is initialized and synced correctly. If it is an equatorial mount, make sure that is accurately polar aligned. This will keep the object centered in the small field of view usually used for high-resolution planetary photography.

Make sure the scope is well collimated and cooled down to the ambient environmental temperature. Check the collimation before every high-resolution planetary imaging session. Collimate on a star close to the subject you plan to shoot. Lock the mirror down and use a Crayford focuser with an SCT. This will greatly reduce the chances of losing collimation when the scope is moved, and make focusing much easier.

Minimize seeing effects both inside the scope, such as tube currents, as well as in the local environment, such as your body heat drifting into the light path. Use a fan to cool your primary mirror. Pick an observing site that minimizes seeing effects such as heat rising off roof tops or asphalt parking lots, warm air falling down into a valley from hills, or turbulent air coming over mountain tops.

Calculate the optimum focal length for sufficient sampling based on pixel size. Use a Barlow lens or eyepiece projection to magnify the image at this focal length.

Take the time to nail the focus. Focus on a star that is nearby with software-assisted metrics, instead of trying to focus on faint low-contrast planetary detail by eye. Re-focus periodically as focus can change, especially if the temperature drops.

Expose correctly. Overexposure leads to loss of highlight detail. Underexposure leads to poor signal-to-noise. Adjust the shutter speed and ISO to adjust the exposure.

Be aware that you have a limited amount of time for shooting a series of frames before planetary rotation will cause detail smearing.

Shoot when the seeing is good. Seeing is not the same as transparency. Often the best seeing is on a warm humid summer night with a temperature inversion and very poor transparency. Check the location of the jet stream, which usually ruins fine planetary detail. Try to shoot on nights when it is not nearby and definitely not overhead. Be patient and wait for periods of good seeing which can occur randomly on a given night.

Use lucky video imaging to shoot a lot of frames. Process in programs like RegiStax, AviStack or AutoStakkert! that will grade and edit the good frames for stacking to improve the signal-to-noise ratio, and sharpen with wavelets to improve the visibility of details.